In a normal lamp, a light source such as light-emitting diode (LED) is generally arranged in a reflecting cup, so as to shape the light emitted from the light source, and/or a lens is used for shaping. For example, FIG. 1 shows a solution in the prior art. In this solution, light sources 1 are arranged in bowls 2. The surfaces of the bowls are coated with a reflective material to function as reflecting mirrors, so that the light output from the light source 1 is nearly a parallel light. An optical lens 3 is arranged over the bowls 2. With the optical lens 3, the angle of the output light may be adjusted to satisfy application requirements. However, because the optical lens which is usually made of resin is used, the lens tends to age in the case of a high power light source, and the service life of the lamp may be shortened. If a lens made of glass is used, the cost in the production technology may be high on one hand, and the lamp may easily be damaged on the other hand. If the power of the light source is reduced to ensure the service life of the lamp, the brightness required by the application may not be satisfied.